examples-barchart.qdoc
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Michal Klocek
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r330 | /*! | ||
Tero Ahola
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r500 | \example examples/barchart | ||
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r387 | \title BarChart Example | ||
\subtitle | ||||
Michal Klocek
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r330 | |||
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r1618 | The example shows how to create a bar chart. BarChart shows the data in sets as separate bars, which are in categories. | ||
Michal Klocek
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Tero Ahola
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r971 | \image examples_barchart.png | ||
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r1618 | |||
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r1859 | The barsets are used in same way in all barcharts. | ||
To illustrate difference between various barcharts, we use same data in examples. | ||||
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r1618 | Data that barchart visualizes, is defined by QBarSet instances. Here we create the sets and append data | ||
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r1859 | to them. The data is appended here with << operator. Alternatively the append method could be used. | ||
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r387 | |||
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r492 | \snippet ../examples/barchart/main.cpp 1 | ||
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r1859 | We create the series and append the barsets to it. The series takes ownership of the barsets. The series groups the data from sets to categories. | ||
Mika Salmela
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r2456 | First values of each set are grouped together at first category second value to second category and so on. | ||
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r492 | \snippet ../examples/barchart/main.cpp 2 | ||
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r1859 | Here we create the chart object and add the series to it. We set the title for chart with setTitle and then turn on animations of the series by calling | ||
setAnimationOptions(QChart::SeriesAnimations) | ||||
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r387 | |||
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r1618 | \snippet ../examples/barchart/main.cpp 3 | ||
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r1859 | To have categories displayed on axis, we need to create a QBarCategoryAxis for that. Here we create a category axis with list of categories and | ||
set it to be the x-axis of the chart. The chart takes ownership of axis. For y-axis we use default axis, which is created and scaled to series data | ||||
by calling createDefaultAxes of the chart. Note that the call for createDefaultAxes must be before we set the category axis. Otherwise the default axis will | ||||
override the category axis. | ||||
Tero Ahola
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r1208 | \snippet ../examples/barchart/main.cpp 4 | ||
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r387 | |||
Mika Salmela
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r2456 | We also want to show the legend. To do that, we get the legend pointer from chart and set it to visible. We also place the legend to bottom of the chart by setting its alignment | ||
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r1859 | to Qt::AlignBottom. | ||
Tero Ahola
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r1208 | \snippet ../examples/barchart/main.cpp 5 | ||
Tero Ahola
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r1859 | Finally we add the chart onto a view. We also turn on the antialiasing for the chartView. | ||
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\snippet ../examples/barchart/main.cpp 6 | ||||
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r1859 | Chart is ready to be shown. We set the chart to be central widget of the window. | ||
We also set the size for the chart window and show it. | ||||
Tero Ahola
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r1618 | \snippet ../examples/barchart/main.cpp 7 | ||
Jani Honkonen
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r1941 | */ | ||